[Nook Color General] pchoi94:
The Reader DOES Matter

Hi all, I wanted to share some interesting results. I returned my 16GB Class 4 to Radio Shack because I wanted a "better" performing card. Costco currently has a sale on the 8GB Class 2 cards, so I picked up 3 of them. I didn't notice until afterward that they actually gave me 2 class 2 cards and 1 class 4 card. No biggie, I was planning to bench them all and return the slowest of the lot anyway. Also it would be interesting to see the results.

Previously I had tested the cards using my phone (HTC Rhodium TP2 Verizon). When I plug the card into the phone and attach it to my laptop via USB there is an option to mount it as a standard drive, like a SD card reader. However, this time I also decided to plug the cards into the Nook itself to compare (mounted as a usb drive as well). The results I got were TOTALLY different. The 8GB class 2 cards seemed to perform SLOWER for random writes via the phone, but WAY FASTER for random writes (and sequential reads) via the nook. Below are my results (btw I decided to bench the Nook's internal EMMC memory as well just for reference):

eMMC Nook Internal

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CrystalDiskMark 3.0.1 x64 (C) 2007-2010 hiyohiyo

Crystal Dew World : http://crystalmark.info/

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* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Sequential Read : 18.000 MB/s

Sequential Write : 4.251 MB/s

Random Read 512KB : 18.918 MB/s

Random Write 512KB : 3.513 MB/s

Random Read 4KB (QD=1) : 4.535 MB/s [ 1107.1 IOPS]

Random Write 4KB (QD=1) : 0.994 MB/s [ 242.6 IOPS]

Random Read 4KB (QD=32) : 5.529 MB/s [ 1349.9 IOPS]

Random Write 4KB (QD=32) : 0.913 MB/s [ 223.0 IOPS]

Test : 50 MB [G: 37.7% (1930.3/5120.1 MB)] (x5)

Sandisk 8GB Class 4 (Costco) [Tested plugged into phone]

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CrystalDiskMark 3.0.1 x64 (C) 2007-2010 hiyohiyo

Crystal Dew World : http://crystalmark.info/

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* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Sequential Read : 5.533 MB/s

Sequential Write : 2.784 MB/s

Random Read 512KB : 5.610 MB/s

Random Write 512KB : 1.306 MB/s

Random Read 4KB (QD=1) : 1.213 MB/s [ 296.2 IOPS]

Random Write 4KB (QD=1) : 0.825 MB/s [ 201.5 IOPS]

Random Read 4KB (QD=32) : 1.194 MB/s [ 291.4 IOPS]

Random Write 4KB (QD=32) : 0.685 MB/s [ 167.3 IOPS]

Test : 50 MB [G: 0.0% (0.1/7572.0 MB)] (x5)

Sandisk 8GB Class 4 (Costco) [Tested plugged into Nook]

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CrystalDiskMark 3.0.1 x64 (C) 2007-2010 hiyohiyo

Crystal Dew World : http://crystalmark.info/

-----------------------------------------------------------------------

* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Sequential Read : 17.586 MB/s

Sequential Write : 5.468 MB/s

Random Read 512KB : 18.740 MB/s

Random Write 512KB : 1.918 MB/s

Random Read 4KB (QD=1) : 4.859 MB/s [ 1186.4 IOPS]

Random Write 4KB (QD=1) : 0.911 MB/s [ 222.3 IOPS]

Random Read 4KB (QD=32) : 6.051 MB/s [ 1477.3 IOPS]

Random Write 4KB (QD=32) : 0.886 MB/s [ 216.3 IOPS]

Test : 50 MB [J: 0.0% (0.5/7572.0 MB)] (x5)

Sandisk 8GB Class 2 (Costco) #1 [Tested plugged into phone]

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CrystalDiskMark 3.0.1 x64 (C) 2007-2010 hiyohiyo

Crystal Dew World : http://crystalmark.info/

-----------------------------------------------------------------------

* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Sequential Read : 5.155 MB/s

Sequential Write : 2.769 MB/s

Random Read 512KB : 5.072 MB/s

Random Write 512KB : 2.395 MB/s

Random Read 4KB (QD=1) : 0.747 MB/s [ 182.3 IOPS]

Random Write 4KB (QD=1) : 0.417 MB/s [ 101.8 IOPS]

Random Read 4KB (QD=32) : 0.715 MB/s [ 174.6 IOPS]

Random Write 4KB (QD=32) : 0.417 MB/s [ 101.9 IOPS]

Test : 50 MB [G: 0.0% (0.1/7572.0 MB)] (x5)

Sandisk 8GB Class 2 (Costco) #1 [Tested plugged into Nook]

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CrystalDiskMark 3.0.1 x64 (C) 2007-2010 hiyohiyo

Crystal Dew World : http://crystalmark.info/

-----------------------------------------------------------------------

* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Sequential Read : 17.590 MB/s

Sequential Write : 4.094 MB/s

Random Read 512KB : 18.752 MB/s

Random Write 512KB : 3.413 MB/s

Random Read 4KB (QD=1) : 4.867 MB/s [ 1188.3 IOPS]

Random Write 4KB (QD=1) : 2.348 MB/s [ 573.2 IOPS]

Random Read 4KB (QD=32) : 5.110 MB/s [ 1247.6 IOPS]

Random Write 4KB (QD=32) : 2.557 MB/s [ 624.3 IOPS]

Test : 50 MB [J: 0.0% (0.5/7572.0 MB)] (x5)

Sandisk 8GB Class 2 (Costco) #2 [Tested plugged into phone]

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CrystalDiskMark 3.0.1 x64 (C) 2007-2010 hiyohiyo

Crystal Dew World : http://crystalmark.info/

-----------------------------------------------------------------------

* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Sequential Read : 5.187 MB/s

Sequential Write : 2.852 MB/s

Random Read 512KB : 5.210 MB/s

Random Write 512KB : 2.475 MB/s

Random Read 4KB (QD=1) : 0.792 MB/s [ 193.4 IOPS]

Random Write 4KB (QD=1) : 0.425 MB/s [ 103.8 IOPS]

Random Read 4KB (QD=32) : 0.713 MB/s [ 174.1 IOPS]

Random Write 4KB (QD=32) : 0.423 MB/s [ 103.2 IOPS]

Test : 50 MB [G: 0.0% (0.1/7572.0 MB)] (x5)

Sandisk 8GB Class 2 (Costco) #2 [Tested plugged into Nook]

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CrystalDiskMark 3.0.1 x64 (C) 2007-2010 hiyohiyo

Crystal Dew World : http://crystalmark.info/

-----------------------------------------------------------------------

* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Sequential Read : 17.605 MB/s

Sequential Write : 4.081 MB/s

Random Read 512KB : 18.752 MB/s

Random Write 512KB : 4.619 MB/s

Random Read 4KB (QD=1) : 4.854 MB/s [ 1185.0 IOPS]

Random Write 4KB (QD=1) : 1.621 MB/s [ 395.7 IOPS]

Random Read 4KB (QD=32) : 5.129 MB/s [ 1252.1 IOPS]

Random Write 4KB (QD=32) : 1.452 MB/s [ 354.6 IOPS]

Test : 50 MB [J: 0.0% (0.5/7572.0 MB)] (x5)

Kingston 16GB Class 2 [Tested plugged into phone]

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CrystalDiskMark 3.0.1 x64 (C) 2007-2010 hiyohiyo

Crystal Dew World : http://crystalmark.info/

-----------------------------------------------------------------------

* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Random Read 4KB (QD=32) : 1.248 MB/s [ 304.6 IOPS]

Random Write 4KB (QD=32) : 0.028 MB/s [ 6.8 IOPS]

Test : 50 MB [G: 0.7% (0.1/14.9 GB)] (x5)

Kingston 16GB Class 2 [Tested plugged into Nook]

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CrystalDiskMark 3.0.1 x64 (C) 2007-2010 hiyohiyo

Crystal Dew World : http://crystalmark.info/

-----------------------------------------------------------------------

* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Random Read 4KB (QD=32) : 5.095 MB/s [ 1243.9 IOPS]

Random Write 4KB (QD=32) : 2.666 MB/s [ 650.9 IOPS]

Test : 50 MB [J: 0.7% (0.1/14.9 GB)] (x5)

As you can see, the results were totally different plugged into the phone vs the Nook. I also decided to re-bench my original Kingston 16GB class 2 card for the heck of it. The first time I benched it in the Nook it gave unusually excellent results, but I couldn't get it to even bench after that (the software would just hang), so I know there's something funky going on there.

So what did I end up doing? Well, I figured that since I'll be using these cards in the Nook anyway, I would rely on the results that the Nook gave me. So I'm keeping the two class 2 cards and returning the class 4.

I've already got the latest nightly (as of yesterday, N97) on there and it seems smoother and faster than it did on my previous 16GB Class 4 sandisk from Radio Shack that I returned, even though I'm not even running an overclock kernel yet (previously I was overclocked to 1200 with smartass governor, now I'm running stock 800Mhz speed with conservative).

I understand it could be a number of things:

1. It's just in my head

2. It's a different build (previously I was running CM7 7.1 beta)

3. I don't have as much crap loaded on it yet, etc. etc. etc.

I guess time will tell. At the very least the results from different methods was interesting. btw, on the second run the sandisk class 2 #2 performed similarly to #1, meaning random writes in the 2.5MB range vs the 1.4 you see there...